T80XB Programming help

[Shift838]

So, i have never messed with T80XB and wanted to get familiar with it.  I need some help as the character definition does not work properly in my code for some reason

 

I am just working on drawing a simple box with the code below.  I have redefined the characters with the CALL LINK("CHAR") command and then using loops to draw the box.  with the corners I am not using a loop, but just a CALL LINK("HCHAR") statement to place the character code in the proper place.  My top and bottom (left corners) work fine as well as the drawing of the top, left and bottom border lines, but when I try to do the same exact thing with the top and bottom right corners it only displays the horizontal piece of the redefined character, and the vertical piece is not there.

 

Note: I have tested the characters codes in standard TI XB and it all displays correctly.

 

Top Right:

Bottom Right

 

When the code is run, it only displays:

I have not put in the drawing of the right border line yet.

100 CALL LINK("T80")
110 CALL LINK("CLS")
120 CALL LINK("CHAR",95,"00000000000000FF")!BOTTOM "_"
130 CALL LINK("CHAR",61,"FF00000000000000")!TOP "="
140 CALL LINK("CHAR",92,"C0C0C0C0C0C0C0C0")!LEFT "\"
150 CALL LINK("CHAR",47,"03FF030303030303")!RIGHT "/"
160 CALL LINK("CHAR",123,"FFC0C0C0C0C0C0C0")!TOP LEFT "{"
170 CALL LINK("CHAR",125,"FF01010101010101")!TOP RIGHT "}"
180 CALL LINK("CHAR",91,"C0C0C0C0C0C0C0FF")!BOTTOM LEFT "["
190 CALL LINK("CHAR",93,"01010101010101FF")!BOTTOM RIGHT "]"
200 GOSUB 21030
210 GOTO 210
21030 FOR X=0 TO 8 :: R=5+X :: C=28 :: X$="\" :: GOSUB 22000 :: NEXT X
21031 CALL LINK("HCHAR",5,28,123):: FOR X=1 TO 28 :: R=5 :: C=28+X :: X$="=" :: GOSUB 22000 :: NEXT X
21032 CALL LINK("HCHAR",14,28,91):: FOR X=1 TO 28 :: R=14 :: C=28+X :: X$="_" :: GOSUB 22000 :: NEXT X
21033 CALL LINK("HCHAR",5,57,125):: CALL LINK("HCHAR",14,57,93):: RETURN
22000 CALL LINK("PRINT",R,C,X$):: RETURN

 

If there is an easier way to do it, then please let me know. 

Edited November 18, 2022 by Shift838

[+jedimatt42]

In 40 and 80 column mode the TI character patterns are 6x8.  So your right hand 2 bits are going to be ignored.

 

 

[Shift838]

1 hour ago, jedimatt42 said:

In 40 and 80 column mode the TI character patterns are 6x8.  So your right hand 2 bits are going to be ignored.

 

 

Learn something new everyday.  I did not know about that.  Thanks Matt!  I figured it was ignoring it but I should have just drawn it 2 bits to the left!  

 

 

[pixelpedant]

Note as well that in 80 column mode, pixels have an extremely stretched aspect ratio.  I discuss my own methods surrounding working with T40XB and T80XB art in my video on developing for T40XB, T80XB, and TMLGA as a component to XB GEM.

 

A key point being that GIMP is able to display pixels at arbitrary aspect ratios on non-square grids.  So a grid of 6x8 tiles whose pixels are twice as tall as they are wide can be worked with there.

 

This is quite necessary, since it would not be realistically possible to design graphics for T80XB directly in Magellan, for example.  Since what you would need to design is the tiles on the right here, in order to achieve the tiles on the left:

 

 

So that's how I made the graphics for my "Still TI" voice synth singing demo, for example.  In GIMP, with 6x8 tiles and a 1:2 pixel aspect ratio. 

 

[GDMike]

When I wanted to make a new char set for my 80 column mode, I had to squeeze into that 6 bit wide range.

Makes character defs a little harder. 

Edited November 19, 2022 by GDMike

[apersson850]

Well, 5 by 7 character definitions are pretty common, and they fit nicely in a 6 by 8 matrix.